Hypertension remains the leading cause of mortality and the third greatest cause of disability worldwide, despite decades of concentrated effort to alter this fact [1]. Thus, the aim of antihypertensive treatment recommended in the European Society of Hypertension (ESH)/European Society of Cardiology (ESC) 2007 guidelines [2] is to reduce an individual’s global cardiovascular risk in order to prevent, halt, or regress the organ damage associated with arterial hypertension. According to the guidelines, blood pressure should be lowered to <140/90 mmHg in all patients with hypertension, whereas in patients with diabetes and patients with cardiovascular disease or renal impairment it is recommended that the blood pressure target be <130/80 mmHg.
In many countries, however, the proportion of patients with acceptable blood pressure control is too low even among those who are diagnosed and treated [3]. Physicians, as well as society, are faced with a difficult choice: Should more resources be invested in treating patients to goal blood pressure or should much higher costs be paid when the consequences of suboptimal control emerge in the form of fatal or disabling cardiovascular events?
The evidence gathered from the vast array of clinical trials gives a clear view of the possible realities. Blood pressure values can be reduced with the appropriate drugs and strategies by using simple follow-up algorithms for treatment if applied with persistence. In the application of the algorithms, more than one drug is often necessary to achieve the blood pressure goal, even in the ideal conditions of the clinical trial scenario with a clear commitment of the physician and active control of the patient´s compliance. The necessity of two or more drugs is the consequence of the mechanisms underlying the blood pressure elevation. Hemodynamics, activity of the renin-angiotensin or sympathetic nervous systems, and total body sodium content largely differs among individuals with essential hypertension. Moreover, it is not easy to identify the main characteristics of each patient when prescribing a more specific antihypertensive treatment in the clinical setting. Furthermore, administration of an antihypertensive drug mainly touches on one of the mechanisms that controls blood pressure, but rapidly the other untouched mechanisms can overreact blunting the blood-pressure-lowering effect of the given drug. Combining two agents with complementary mechanisms of action can provide blood pressure control that is not only effective, but also rapid.
Beside the mentioned pathogenic mechanisms, lack of application of proper therapeutic algorithms by the physicians and weak adherence to treatment by patients are also among the important factors that contribute to insufficient blood pressure control, such as been recognized in a recent white paper [4]. Clinical inertia is common, and persistence with antihypertensive therapy declines substantially within the fi rst year of treatment [5]. Awareness of the risk by both physicians and patients, as well as simplification of treatments, can help to increase the rate of success.
Simplification of treatments has been recognized as one of the most successful interventions to improve adherence to antihypertensive treatment according to a Cochrane Cooperation Study [6]—reducing the number of pills is one important step in this simplification. However, because treatment with a single agent is often insufficient and the majority of patients require combination therapy with two or more antihypertensive agents from different classes [2,7], the requirement for multiple agents makes the task of ensuring patient compliance with therapy extremely challenging.
One simple solution is to consider a fixed-dose combination to improve adherence and obtain more rapid blood pressure control [2,7]. Fixed-dose combinations can help to overcome adherence issues [6] and are recommended in treatment guidelines [2,7]. Combinations should be synergistic, improving the efficacy of a treatment and reducing side effects, both of which contribute to a more effective treatment [8,9]. There is no shortage of agents to choose from, and physicians can refer to robust data and well-designed guidelines to support their choices.
The majority of fixed-dose combinations are based on beta-blockers, angiotensin-converting enzyme inhibitors, or angiotensin II receptor blockers, combined with thiazide diuretics or calcium channel blockers. In the present issue of Hot Topics in Hypertension, the fixed-dose combination of olmesartan medoxomil/amlodipine is reviewed in detail. Beside the potent antihypertensive activity of the combination, its importance becomes greater in light of the results of the recent Avoiding Cardiovascular Events in Combination Therapy in Patients Living with Systolic Hypertension (ACCOMPLISH) trial [10], in which the combination of benazepril with amlodipine was superior to the combination of hydroclorothiazide and benazepril in terms of reducing cardiovascular events; it should be noted that these results were obtained in a population with a high prevalence (60%) of type 2 diabetes. While future studies will help delineate the best strategy according to the individual characteristic of each patient, it is clear that the combination of olmesartan medoxomil/amlodipine can become an important tool in antihypertensive treatment.

 

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